Warm 1/2 cup of the vanilla-flavored milk (do not boil) until steaming — about 30–45 seconds in a microwave or gently on the stovetop. Add the 1/2 tsp dried culinary lavender buds, remove from heat, cover, and steep for 10 minutes to infuse. After steeping, strain out the lavender buds through a fine-mesh sieve, pressing gently to extract liquid. Chill the infused milk completely in the refrigerator (or use an ice bath) until cold — about 10 minutes.

Prepare matcha concentrate for foam

Sift 1 tsp matcha powder into a small bowl. Add 2 tbsp cold water and whisk briskly in an 'M' or 'W' motion until smooth and frothy with no clumps (about 20–30 seconds). Stir in 1 tbsp simple syrup and 1/4 tsp vanilla extract into the matcha slurry until combined.

Make the cold foam

Combine the chilled lavender-infused milk, the remaining 1/2 cup vanilla milk, and 1/4 cup heavy cream in a tall jar or milk frother. Add the prepared matcha-syrup mixture. Secure the lid and froth with an electric milk frother until dense microfoam forms (30–45 seconds). If you don't have a frother: pour into a blender and pulse on high for 10–15 seconds, or vigorously shake in a sealed jar for 45–60 seconds. Taste and adjust sweetness with extra simple syrup if needed.

Iced Latte Assembly

Fill a 16-oz glass with 1 cup of ice.

Pour 1/2 cup cold-brewed green tea over the ice. This provides a subtle green-tea body and keeps the drink light; if you prefer a stronger matcha flavor, substitute the cold-brew with an additional 1/2 cup milk and omit the optional syrup.

If desired, add 1 tsp additional simple syrup to the cold-brew and stir to combine.

Slowly spoon the prepared matcha lavender cold foam over the iced base, allowing it to float on top and create a layered appearance. Use a spoon to help control the pour for best presentation.

Garnish with a light dusting of 1/8 tsp matcha powder and a pinch (1/8 tsp) of dried lavender buds on top of the foam, if using. Serve immediately with a straw or long spoon.